diff --git a/content/treestyletab/res/fullScreenCanvas.xul b/content/treestyletab/res/fullScreenCanvas.xul
index ea8d0053..2ed62976 100644
--- a/content/treestyletab/res/fullScreenCanvas.xul
+++ b/content/treestyletab/res/fullScreenCanvas.xul
@@ -57,27 +57,34 @@ window.addEventListener('DOMContentLoaded', function() {
 					var h = frame.innerHeight;
 					var dx = 0;
 					var dy = 0;
-					if (TST &&
+					if (
+						TST &&
 						TST.autoHideEnabled &&
-						TST.autoHideShown) {
+						('autoHideShown' in TST ? 
+							TST.autoHideShown :
+							TST.tabbarShown
+						)
+						) {
 						var pos = b.getAttribute(TST.kTABBAR_POSITION);
+						var xOffset = 'autoHideXOffset' in TST ? TST.autoHideXOffset : TST.tabbarWidth ;
+						var yOffset = 'autoHideYOffset' in TST ? TST.autoHideYOffset : TST.tabbarHeight ;
 						switch (pos)
 						{
 							case 'left':
-								dx = TST.autoHideXOffset;
-								w -= TST.autoHideXOffset;
+								dx = xOffset;
+								w -= xOffset;
 								break;
 							case 'right':
-								x += TST.autoHideXOffset;
-								w -= TST.autoHideXOffset;
+								x += xOffset;
+								w -= xOffset;
 								break;
 							case 'top':
-								dy = TST.autoHideYOffset;
-								h -= TST.autoHideYOffset;
+								dy = yOffset;
+								h -= yOffset;
 								break;
 							case 'bottom':
-								y += TST.autoHideYOffset;
-								h -= TST.autoHideYOffset;
+								y += yOffset;
+								h -= yOffset;
 								break;
 						}
 					}